Furan resin compositions including tall oil and an aromatic aldehyde



United States Patent @fiice 7 2,868,747 Patented Jan. 13, 1959 FURANRESIN COMPOSITIONS INcLUDrNG TALL OIL AND AN AROMATIC ALDEHYDE RaymondM. Frey, Hales Corners, Wis., assignor to McGraw-Edison Company, acorporation of Deiaware NoDrawing. Application November 4, 1955 SerialN0. 545,110

9 Claims. (Cl. 260-235) aldehyde, such as benzaldehyde, in combinationwith tall oil.

Another object of the invention is to provide a new resinousthermosetting composition by effecting reaction between a furancompound, tall oil and an aromatic aldehyde selected from a groupconsisting of benzaldehyde, cinnamaldehyde, p-hydroxy benzaldehyde,salicylaldehyde and naphthaldehyde.

It is well known that furan resins may be polymerized to providecharacteristics of exceptional physical strength and shock resistance,in addition to having superior chemical resistance to alkalies, acidsand ordinary solvents. It is also Well known that furan compounds havebeen successfully reacted in simple conden sation procedures with otheringredients such as phenols or various aldehyde compounds to provide aresin having certain desired characteristics. I

In my copending application, Serial No. 340,281, filed March 4, 1953,which was granted on February 21, 1956, as Patent No. 2,735,826, I havedisclosed as a new composition of matter, certain furan compositions andthe process for preparing the same, wherein tall oil in either a crudeor refined state, may be included as an ingredient of a basic furanresin composition. The addition of tall oil, as disclosed therein, actedto extend or modify the basic furan composition to provide a productthat is simple to control in its exothermic condensation reaction, lessexpensive to prepare, which provides the same desirable characteristicsof the basic furan resin, and which may be cast or pressure-molded andfilled prior to complete curing with various molding compositionfillers.

The present application is directed to the addition of tall oil to afuran-aromatic aldehyde reaction to provide a new composition of matterand to the process for preparing such composition.

The reaction appears to be electrophillic in nature and accordingly, isresponsive to the well-known Lewis acid catalyst. These acid catalystshave been fully described as to their nature and action on page 80 ofthe treatise, Advanced Organic Chemistry, 2nd ed., by G. W. Wheland,Wiley and Sons, Inc., New York.

It is to be noted that tall oil, in its crude state, includes from 40 to60% fatty acids and 35 to 50% rosin acids, wherein the fatty acids areprincipally unsaturated and comprise oleic acid, linoleic acid andlinolenic acid. In the reactions of the furan compound, aromaticaldehyde and tall oil, the only side compound formed, which did notsubsequently combine with the final product, was water, a naturalproduct of the condensation reaction. Though it is not entirely clearthat all of the ingredients chemically reacted with one another toprovide the thermosetting compound, it is at least apparent that theaddition of the tall oil combines to act as a helpful extender havinglittle or no effect on the final desired characteristics of the basicfuran resin.

The resulting product of my invention is an improved furan resin whichmay be cast directly or which may be filled with various materials underpressure molding conditions and having excellent physical strength andshock resistance. The resultant material may be used in any manneracceptable for use with the well-known furfuryl alcohol resins.

Aside from using benzaldehyde as an ingredient, numerous other aromaticaldehydes have been successfully reacted with a furan compound and talloil. Examples of these are cinnamaldehyde, p-hydroxy benzaldehyde,salicylaldehyde (o-hydroxy benzaldehyde), and naphthaldehyde.

Typical examples of carrying out the, present invention are given below:

Example I (a) A 3:221 ratio of furfuryl alcohol, crude tall oil andbenzaldehyde were reacted together using 60 gms. of alcohol, 40 gms. ofcrude tall oil and 20 gms. of benzaldehyde. These materials were addedtogether at room temperature in the presence of about 2% of diethylsulfate as the catalyst. The mixture was heated on a water bath fromroom temperature to approximately 180 F., at which point an exothermicreaction took place. The exothermic reaction provided a temperature riseof approximately 50 F. The mixture was then removed from the water bathand permitted to cool to a temperature of approximately 180. Heat wasthen applied to maintain the 180 F. temperature within plus or minus 5degrees to permit polymerization to take place. The polymerizationproceeded until the material thickened to the desired castingconsistency. After casting into a suitable shape, the cast object wasplaced in an oven and maintained at a temperature of approximately 180F. for final curing.

(b) The ingredients were processed in substantially the identical mannerset forth above, with the exception that they were reacted together in a1:1:1 ratio by weight. The resultant product was also very acceptable,in that it produced a thermosetting resin of excellent strength withoutindication of any leaching out of the reactants on final curing.

(c) The same ingredients were again reacted in the same manner asdescribed above, except that a ratio of 3:2:2 by weight of furfurylalcohol, crude tall oil and benzaldehyde were reacted together with 2%by weight of total mix of the diethyl sulfate catalyst. Again, thethermosetting resin obtained after final curing was very hard, uniformand shiny.

Example 2 (a) 60 gms. of furfuryl alcohol, 40 gms. of crude tall oilwere mixed with 20 gms. of cinnamaldehyde:

CH=CHOHO The mixture also included about 2% diethyl sulfate strong.

3 Example (a) 60 gms. of furfuryl alcohol, 40 gms. of tall oil weremixed in the presence of diethyl sulfate as a catalyst: with 40 gms. ofp-hydroxy*benzaldehydei "L CHO Example 4 60 gms. of furfuryl alcohol, 40gms. of tall oil were mixed in the presence of 2% diethyl sulfate withthe aromatic aldehyde, salicylaldehyde:

CHO

-The above ingredients were mixed according to the process set forth inExample 1 and produced a thermosetting resin which was uniform inconsistency and had a shiny surface.

Example 5 In the present example, 60 gms. of furfuryl alcohol and 40gms. of tall oil were admixed with 40 gms. of naphthaldehyde CHO Thereaction took place in the presence of 2% diethyl sulfate as a catalyst,and again produced a thermosetting. resin which was uniform inconsistency.

It will be apparent that the present invention has provided an improvedfuran resin and method for its preparation, wherein the addition of talloil as a helpful extender contributes to a considerable cost reductionwith out any way detrimentally afiecting the excellent chemi' cal andphysical characteristics of the basic composition.

I claim:

1. A method of preparing a thermosetting resin including the steps ofadmixing from 1 to 3 parts of a furan compound selected from the groupconsisting of furfural and furfuryl alcohol, 1 to 2 parts tall oil, and1 to 2 parts of an aromatic aldehyde, in the presence of diethyl sulfateas a catalyst, heating the mixture until thickened by resinification,and heat curing the thickened mixture to a thermosetting state.

'2. The method of claim 1, wherein the aromatic aldehyde isbenzaldehyde.

3. The method of claim 1, wherein the ingredients are combined in a3:2:1 ratio by weight of furfuryl alcohol, tall oil and benzaldehyde,respectively.

4. The method of claim 1, wherein the ingredients are combined in a1:121 ratio by weight of furfuryl alcohol, tall oil and benzaldehyde,respectively.

5. The method of claim 1, wherein the ingredients are combined in a3:2:2 ratio by weight of furfuryl alcohol, tall oil and benzaldehyde,respectively.

6. The method of claim 1, wherein the aromatic aldehyde iscinnamaldehyde.

7. The method of claim 1, wherein the aromatic alde hyde is p-hydroxybenzaldehyde.

8. The method of claim 1, wherein the aromatic aldehyde issalicylaldehyde.

9. The method of claim 1, wherein the aromatic aldehyde isnaphthaldehyde.

References Cited in the file of this patent UNITED STATES PATENTS

1. A METHOD OF PREPARING A THERMOSETTING RESIN INCLUDING THE STEPS OFADMIXING FROM 1 TO 3 PARTS OF A FURAN COMPOUND SELECTED FROM THE GROUPCONSISTING OF FURFURAL AND FURFURYL ALCOHOL, 1 TO 2 PARTS TALL OIL, AND1 TO 2 PARTS OF AN AROMATIC ALDEHYDE, IN THE PRESENCE OF DIETHYL SULFATEAS A CATALYST, HEATING THE MIXTURE UNTIL THICKENED BY RESINIFICATION,AND HEAT CURING THE THICKENED MIXTURE TO A THERMOSETTING STATE.